Locking device, especially for motor vehicle locking

ABSTRACT

The invention is directed to a locking device with a locking cylinder which is formed of a cylinder guide and a cylinder core which is rotatably supported therein. When the key is withdrawn, the cylinder core is locked with the cylinder guide via spring-loaded tumblers. The cylinder guide is rotatably supported in the housing, but is fixed with respect to rotation therein via a catch when the key is rotated. When the key is inserted, the rotation of the cylinder core is transmitted, via a radially spring-loaded and radially displaceable radial slide, to a driver performing the locking functions in the lock. The catch has a push-rod by means of which the spring-loaded radial slide can be controlled so that the transmission of torque to the driver is interrupted when the locking cylinder is forcibly rotated. In a suggestion for a compact construction of the device with the fewest components possible, the radial slide is guided radially in the driver so that it is fixed with respect to rotation relative to the driver. Coupling faces are provided between the radial slide and the cylinder core and stop faces are provided between the radial slide and the housing. The radial slide is controlled such that it engages either with the coupling faces or with the stop faces of the housing.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention is directed to a locking device with a locking cylinder,especially for a motor vehicle. In such device the key-operated rotationof the cylinder core is transmitted from a radial slide to a drivercooperating with lock elements, but is interrupted in the region of thedriver when the locking cylinder is rotated by force because the latteris displaced by a push-rod against the force of a spring acting upon it.The push-rod is part of an overload catch having, in the adjoiningstructural component parts, a radial opening which encloses the push-rodand a radial recess which receives only the radial end of the push-rod.The radial recess is defined by stop cams which lift the end of thepush-rod out of the radial recess during a rotation of the structuralcomponent part. Aside from controlling the radial slide, the push-rodhas the function of fixing the cylinder guide in the housing when thecylinder core is rotated by means of the key, but causing the cylinderguide to run freely when the locking cylinder is rotated forcibly via aburglary tool or the like.

2. Description of the Related Art

In a known device of this type, DE-PS 40 41 134 C1, a radial slide isguided in the cylinder core so as to be displaceable. The push-rodbelonging to the overload catch is pressed outward radially from theaxis of the cylinder core by the spring loading of the radial slidesince the radial recess for receiving the end of the push-rod isarranged at the inner surface of the housing which faces the cylinderguide. The radial slide projects axially beyond the inner end of thecylinder core and normally engages with coupling faces of the driver.When the overload catch is in its free-running position, the radialslide is displaced toward the axis of the cylinder core by the push-roduntil it disengages from the coupling faces of the driver. In order toblock the driver in the free-running position, an additional thrust baris required in the driver and must be controlled by an axial pin of theradial slide. This axial control pin calls for a removal of materialfrom the driver to allow for the radial movement of this control pin.

This known device is formed of numerous structural component partsnecessitating tedious assembly and requiring considerable space. Areliable connection between the locking bar, which is displaceable inthe driver, and the radial slide in the cylinder core is difficult. Arelatively large clearance is required for unimpeded cooperation of thestructural component parts.

In a locking device of a different type, EP 0 444 972 B1, the cylindercore which supports the spring-loaded tumblers is rotatably supporteddirectly in the housing rather than in a cylinder guide. Therefore,there is also no push-rod which belongs to the overload catch and whichis lifted out of a radial recess likewise belonging to the overloadcatch when a determined torque is exerted on the cylinder core and whichaccordingly sets the overload catch in its free-running position.Although there is a spring-loaded radial slide in this known lockingdevice, this radial slide is positively controlled by a swivelablelocking bar. The swivel axis of the locking bar is situated at thecylinder core and its head which is provided with a feeling nose engagesin an axially parallel cut out portion of the cylinder core. This cutout portion extends up to the tumblers that are arranged in the cylindercore and controlled by the key. The tumblers must have additionallateral notches. The notches in the individual tumblers are so arrangedthat they are axially aligned with one another when the proper key isinserted into the cylinder core. The feeling nose of the locking bar candrop into the notches. A finger which extends as an axial continuationof the locking bar head drops into a radial groove of the driver (FIGS.3, 7) or of the cylinder core (FIG. 11) and moves the radial slide intoa coupling position with respect to the driver. A rotation of thecylinder core can then be transmitted to the driver via the finger ofthe swivelable locking bar. If the key inserted into the cylinder coreis not the proper one, at least some notches of the tumblers will not bealigned with the locking bar nose and the locking bar is in a positionin which it is swiveled away from the cylinder core and the locking barfinger presses the radial slide into a position in which it is uncoupledfrom the driver.

This known locking device has relatively numerous, complicatedstructural component parts which can cause problems during operation andrequire costly individual manufacture and assembly. Conventionalcylinder cores with cylinder guides cannot be used. Rather, specialshapes with integrated bearings for the locking bar and speciallongitudinal grooves for penetration by the feeling nose of the lockingbar are required. Further, the tumblers also require a special form,namely the arrangement of additional notches which must be adapted tothe control surfaces for the key. All of this renders the manufacture ofsuch locking devices expensive. This known locking device does not offerany suggestion of how to develop a control for a locking device where anoverload catch is provided in addition to the cylinder guide.

OBJECT AND SUMMARY OF THE INVENTION

The primary object of the present invention is to develop a compactlocking device of the type where an overload catch is provided inaddition to the cylinder guide with few structural component parts andwith reliable action.

In accordance with the invention, which is designed to meet the statedobject, in a locking device with a locking cylinder, especially formotor vehicle locking, the locking cylinder has a cylinder guide and acylinder core which is rotatably supported therein so as to be fixedaxially and serves to receive a key and can be locked with the cylinderguide via spring-loaded tumblers when the key is withdrawn. The cylinderguide is rotatably supported in a stationary housing, but fixed withrespect to rotation therein via an overload catch which is brought intoan effective position. The overload catch has a floating push-rod, aradial opening enclosing the push-rod, and a radial recess where adetermined torque is exerted on the cylinder guide and accordingly setsthe overload catch in a free-running position. When the inserted key isrotated, the cylinder core transmits the torque, via a radiallydisplaceable and radially spring-loaded radial slide, to a driver whichperforms the locking functions in the motor vehicle. The radial slidehas a stop face for the push-rod and presses the push-rod into theradial recess of the overload catch due to its spring loading. Thepush-rod, which is lifted out of the radial recess at a determinedtorque displaces the radial slide. The locking device has an improvementwhich comprises that the radial slide is guided radially in the driverso as to be fixed with respect to rotation relative thereto. Further,coupling faces are provided between the radial slide and one of acylinder core and a core pin forming an extension of the core. Stillfurther, stopping surfaces are provided between the radial slide and thehousing. The improvement also comprises that the radial slide engageswith either the coupling faces of the cylinder core or with the stoppingsurface of the housing; the radial spring loading between the driver andthe radial slide presses the push-rod in the direction of the rotationalaxis of the cylinder core and holds the overload catch in its effectiveposition.

In the invention, the radial slide is guided directly in the driver andcooperates directly with the coupling faces of the cylinder core or withthe stopping surfaces of the housing. The control of the radial slide iseffected via the push-rod of the overload catch which is pressed in thedirection of the rotational axis of the cylinder core by the springloading of the radial slide. Thus, the overload catch is always in theeffective position, where the cylinder guide enclosing the cylinder coreis fixed with respect to rotation in the housing. The invention allowsfor a compact, space-saving construction working in a trouble-freemanner.

In the invention, the cylinder guide is a component part of the overloadcatch and has either the radial recesses for the end of the push-rod orthe radial opening for the floating push-rod. In the former case, theoverload catch is constructed in the manner of a clutch release systemwhich is indicated more fully in claim 2 and is shown in the embodimentexample in FIGS. 1 to 7. Other details are indicated in claim 3. In thelatter case, the overload catch is constructed in the manner of a clutchengaging system as is explained more fully with reference to FIGS. 8 to13.

Further steps and advantages of the invention are indicated in the restof the claims, the following description, and the drawings. Theinvention is shown in two embodiment examples in the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a schematic longitudinal section through a first embodimentform of the locking device, according to the invention, when the key isinserted and the cylinder core is in its neutral position in which thekey can be inserted and withdrawn;

FIGS. 2 and 3 show a cross-sectional view through the device alongsection line II--II and III--III of FIG. 1, wherein the key has not yetbeen inserted in FIG. 3;

FIG. 4 shows a front view of the device shown in FIG. 1 with a sectionthrough the key shank along section line IV-IV of FIG. 1;

FIG. 5 shows a longitudinal section through this device corresponding toFIG. 1 when an overload protection has been brought into thefree-running position due to a forcible rotation of a burglary tool;

FIG. 6 shows a cross section corresponding to FIG. 2 through the devicein the free-running position shown in FIG. 5;

FIG. 7 shows a front view of the device corresponding to FIG. 4 with asection through the burglary tool along section line VII--VII from FIG.5;

FIG. 8 shows an axial section through a second locking device accordingto the invention which is also shown only schematically, wherein thecylinder core is in the neutral position prior to the insertion of thekey;

FIG. 9 shows another schematic cross section through the device alongthe offset section line IX--IX of FIG. 8;

FIG. 10 shows the front view of the device from FIG. 8 as seen in thedirection of arrow X in FIG. 8;

FIG. 11 shows an axial section corresponding to FIG. 8 through thisdevice, but after the key has been inserted and turned somewhat;

FIG. 12 shows the conditions along section line XII--XII of FIG. 11resulting after the rotation of the key as shown in FIG. 11 in asectional view corresponding to FIG. 9; and

FIG. 13 shows the front view of the device from FIG. 11 in sectionthrough the key along section line XIII--XIII corresponding to FIG. 10.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The first embodiment form of the locking device, according to theinvention, which is shown in FIGS. 1 to 7 is preferably installed inmotor vehicles and comprises a locking cylinder which is formed of acylinder guide 20 and a cylinder core 10 which is rotatably supportedtherein so as to be fixed axially. This axially fixed connection isrepresented by inner stepped surfaces between a guide bush 21 forming anaxial prolongation of the cylinder guide 20 and a core pin 11 forming anaxial lengthening of the cylinder core 10. Also associated therewith isa widened head 12 at the cylinder core which is supported at the frontend of the cylinder guide 20. The cylinder core 10 has a key groove 13shown in FIGS. 3 and 4 for receiving a key 14 shown in FIG. 1 and afamily of spring-loaded tumblers 15 which can be seen most clearly fromFIG. 3 because the key 14 has been removed in this figure. When the key14 is not inserted in the cylinder core 10, the tumblers 15 are pressedoutward radially because of the spring loading and engage in a catchgroove 25 as will be seen from FIG. 5. In the embodiment example shownin the drawing, two catch grooves 25 are located opposite one another.The tumblers 15 which exit from the cylinder core 10 diametricallyopposite one another move into the catch grooves 25 and lock thecylinder core 10 in the cylinder guide 20.

The cylinder guide 20 is rotatably supported per se in a stationaryhousing 30, but, according to FIG. 2, is normally fixed with respect torotation in the housing 30 via an overload catch 60 which will bedescribed more fully hereinafter. The cylinder guide 20 is positioned inthe housing 30 so as to be fixed axially so that the cylinder core 10 isalso fixed axially in the housing 30 via the axially fixed connectionmentioned above. A driver 50 is rotatably supported on its core pin 11and is arranged at a defined distance from the housing 30 via a snapring 56. The driver 50 has an arm 51 which can execute the desiredlocking functions in the motor vehicle via additional lock elements, notshown.

The driver 50 is held in a defined initial rotational position by meansof an impulse spring 32 which is represented in FIG. 1 by the arm 51shown by a solid line. This impulse spring 32 has two substantiallyradially extending spring legs 31 which penetrate two openings 33 in thehousing 30 and enclose between them on either side a finger 52 which isprovided at the driver 50. Between the two openings 33 there is formed ahousing web 34 at which the driver finger 52 is held by the spring legs31 in a springing manner in the direction of the two arrows 36representing the spring force. This initial rotational position of thedriver 50 also affects the cylinder core 10 for reasons to be explainedhereinafter.

A radial slide 40 is guided at the driver 50 in the displacementdirection indicated by arrow 41 shown in FIG. 1 and is therefore alwaysconnected with the driver 50 so as to be fixed with respect to rotationrelative thereto. This guide 55 in the driver 50 is shown in FIG. 5. Aradial spring loading in the force direction indicated by arrow 53 shownin FIG. 1 acts on the radial slide 40. This is effected by a pressurespring 54 in a recess supported at both ends at radial stepped surfacesbetween the driver 50 and the radial slide 40. The slide 40 isaccordingly pressed in the direction of the cylinder is longitudinalaxis 17 shown in dash-dot lines in FIG. 1 and, as is shown in FIG. 1,brings about the engagement of the coupling faces 16, 46 which can beseen most clearly in FIG. 5. In the present case, these coupling facesare formed of a radial projection 46 at the radial slide 40 and a radialdepression 16 in the circumferential surface 18 of the core pin 11. Theinitial rotational position of the driver 50 described above isaccordingly transmitted to the cylinder core 10 via the slide 40 and theengaged coupling 16, 46. The cylinder core 10 is therefore also held bymeans of the impulse spring 32 with reference to the key groove 13 ofFIG. 4 in the "neutral position" represented by the auxiliary line N.

In this neutral position N shown in FIG. 4, the proper key 14 can beinserted into or withdrawn from the cylinder core 10. In the insertedstate of the key 14, the tumblers 15 are aligned on the circumference ofthe cylinder core 10 as is shown in dashed lines in FIG. 1. The cylindercore 10 is then rotatable in the cylinder guide 20. When the key 14 isactuated in the rotational direction indicated by the arrow 19 shown inFIG. 4 into one or more of the working positions which are angularlyoffset relative to one another, one of which is represented by auxiliaryline A in FIG. 4, the driver 50 is also rotated along via the coupledradial slide 40, which is shown in FIG. 4 by a corresponding rotationarrow 59. The driver arm 51 which is first located in the correspondingneutral position N according to FIG. 4 is accordingly swiveled into thecorresponding working position 51' shown in dash-dot lines in FIG. 4 inwhich the connected lock elements, which were already mentioned above,execute the desired locking functions in the motor vehicle. When the key14 is released, the driver 50 and accordingly also the cylinder core 10move again into the neutral position N shown in FIGS. 2 and 4 by meansof the impulse spring 32.

Instead of the cylinder rotation 19 according to FIG. 4, the cylindercore 10 could also be rotated in the opposite direction as indicated bythe dotted arrow 19' via the key 14 in order to move it into analternative working position A' which is likewise shown in dashed linesin FIG. 4. Naturally, during this opposite rotation 19' the driver alsoexecutes the opposite rotation of its arm 51 as is shown by thecorresponding dotted arrow 59' in FIG. 4. The arm 51 is indicated by thecorresponding dotted auxiliary line A'.

The overload catch 60, mentioned above, serving to fix the cylinderguide 20 with respect to rotation in the housing 30 has the specialconstruction which is shown in FIGS. 1 and 2. This construction is madeup in part by a floating push-rod 61 which is constructed in the presentinstance as a roller 61. This roller 61 is enclosed by a radial opening37 which, in this embodiment example, is located in an inner sleeve 38belonging to the housing 30. The described impulse spring 32 is coiledaround this inner sleeve 38 of the housing. The overload catch 60 alsocomprises a radial recess 27 in which the roller 61 normally engages byits inner radial end. This occurs as a result of the described springloading 53 of the pressure spring 54 by means of a stop face 42 which isprovided at the radial slide 40. As will be seen from FIG. 2, this stopface 42 extends in the rotating direction 19 and 19' of the key-actuatedrotation shown in FIG. 4. That is, the spring-loaded stop face 42 islocated at the cylindrical outer surface 57 of the inner sleeve 38 ofthe housing, while the radial recess 27 of the cylinder guide 20 of theopposite inner surface 38 faces this inner sleeve 38 of the housing. Theradial recess 27 is worked into the circumferential surface of the guidebush 21, already mentioned above, which forms an axial extension of thecylinder guide.

If required, the cylinder guide 20 can also be fixed with respect torotation in the housing 30 by means of an additional catch holder 22,23. As is shown in FIGS. 1 and 3, this is formed of a catch projection22 which, in this instance, is simply a movable roll. The complementaryelement of the catch holder is formed of a catch depression 23 which isincorporated in the outer surface 24 of the cylinder guide 20. The roll22 is located in a wall bore hole 26 of the housing 30 and is pressedinward in the direction of force indicated by the arrow 49 shown in FIG.3 by a leaf spring 29 located at the housing circumference. Thus, theroll 22 normally engages with the catch depression 23 and fixes adefined rotational position of the cylinder guide 20 in the housing 30.However, the rotational position is also fixed by means of the overloadcatch 60 mentioned above. This only changes when violent force isapplied according to FIGS. 5 to 7.

FIG. 5 illustrates the attempt on the part of an unauthorized person notin possession of the proper key 14 to break open the locking deviceaccording to the invention. For this purpose, a burglary tool 62, e.g.,the tip of a screwdriver according to FIG. 7, is inserted into the keygroove 13 of the cylinder core 10 and forcible rotation 62 illustratedin FIG. 5 is applied to the cylinder core 10. In this case, however, aswas already mentioned, the tumblers 15 are in the locking position withthe cylinder guide 20, so that the entire locking cylinder 10, 20 issubjected to the forcible rotation 62. In FIGS. 5 and 6, a small initialrotation shown in FIG. 7 is to be effected in the rotating directionshown by the arrow 63 in FIG. 7. This results in the situation shown inFIG. 6. The radial recess 27 in the guide bush 21 of the cylinder guide20 is defined in the direction of the forcible rotation 62 by stop cams28 which face toward the above-mentioned inner surface 58 of the innersleeve 38 of the housing. The roller 61 consequently runs against thecorresponding stop cam 28 and is accordingly lifted out of the radialopening 27. In so doing, the roller 61 moves in the vertical plane ofthe housing 30 determined by the radial opening 37 and presses againstthe stop face 42 of the radial slide 40. The radial slide 40 isaccordingly set radially outward in the displacement direction indicatedby the arrow 61 shown in FIG. 6 against the spring loading 53 of thepressure spring 54. The guide bush 21 of the cylinder guide 20 is nowfree so that the above-mentioned forcible rotation 62 of the entirelocking cylinder 10, 20 can take place. The overload catch 60 is in thefree-running state.

The limiting torque which sets the overload catch 60 in the free-runningstate is determined on the one hand by the given pretensioning of thepressure spring 54 and on the other hand by the inclination of the stopcams 28 of the locking radial recess 27. Naturally, the catch holder 22,23 described with reference to FIG. 3 is also released in thefree-running situation. As will be seen from FIG. 5, the roll 22 ispressed outward radially out of the catch depression 23 into thecylinder guide 20 against the tension of the leaf spring 29 in themovement direction indicated by the arrow 64. Apart from the slightinitial rotation 63 which is required for moving the roller 61 into thefree-running position of the overload catch 60 shown in FIG. 6, thecontinuing forcible rotation 62 of the cylinder guide 10, 20 is nolonger transmitted to the driver 50 as in FIGS. 1 to 4 for reasonsexplained hereinafter.

During the displacement 41 of the radial slide 40 in the guide 55 of thedriver 50 according to FIG. 6, the cooperating coupling faces 16, 46 aremoved into their uncoupled position shown in FIG. 5. The forciblerotation 62, which also has an effect in the core pin 11, canaccordingly no longer be transmitted to the driver 50. The driver arm 51according to FIG. 7 remains stationary during the rotational movement 62apart from a slight oscillation 65 when the roller 61 is lifted outduring the initial rotation 63. The locking functions in the lock are sodimensioned that these oscillations 65 of the driver arm 51 have noeffect. At all events, it is important that the rotation of the driverarm which is decisive for an adjusting movement of the lock elements inthe motor vehicle and is illustrated by the dashed arrow 66 in FIG. 7does not enter the working position represented by the auxiliary line A.

Further, during the free-running of the overload catch 60 the driver 50is in a locking position which is also caused by the radial slide 40. Inaddition, as is shown most clearly in FIGS. 1 and 2, the radial slide 40has a locking tongue 44 with stopping surfaces 45 on both sides. Thehousing 30, specifically its outer sleeve 39, has the respectivecounter-stopping surfaces 35 which are formed by a corresponding housingrecess 67. When the overload catch 60 is active, as is shown in FIGS. 1and 2, the stopping surfaces 35, 45 are in a release position. However,when the overload catch 60 is in the free-running position according toFIGS. 5 and 6, the locking tongue 44 moves into the housing recess 67.The stopping surfaces 35, 45 on both sides are then in their lockingposition. The radial slide 40 is then blocked in the housing 30. It isnot possible to manipulate the driver arm 51 in order to carry out thecritical arm rotation 66 described above with reference to FIG. 7. Aforcible break-in has no effect on the locking device according to theinvention.

An alternative device according to the invention is shown in theembodiment example in FIGS. 8 to 13. To the extent that the precedingdescription also applies in part to this alternative device, the samereference numbers will be used. The discussion will be restricted to thedifferences between the embodiment examples, principally in the regionof the corresponding radial slide 40' and the overload catch 60'. Inorder to show the differences in operation more clearly, a stroke (') isadded to the reference numbers to distinguish them from those used inthe first embodiment example according to FIGS. 1 to 7.

The first embodiment example of FIGS. 1 to 7 is directed to an overloadcatch 60 which fixes the cylinder guide 20 in the housing 30 in theneutral position N according to FIGS. 1 to 4. As was already described,this remains so during the key rotation 19 and 19' according to FIGS. 2and 4. As was already described, the free-running of the cylinder guide20 first resulted from the forcible rotation 62 of the cylinder guide 20according to FIGS. 5 and 6. Very different and, in tart, oppositeconditions apply in this respect to the overload catch 60' of the secondembodiment example shown in FIGS. 9 to 13. In the neutral position ofthe cylinder core 10 shown by the auxiliary line N in FIG. 10, thecylinder guide 20 is already in a free-running position in the housing30 regardless of whether or not a key is inserted. However, the cylinderguide 20 is first locked in its neutral position N, specifically, apartfrom the catch holder 22, 23 which is also provided in this secondembodiment example and was already described above with reference toFIG. 3, primarily by means of the overload catch 60' which in this caseis constructed in the manner described hereinafter.

The corresponding roller 61' of this overload catch 60' which functionsas a floating push-rod is located, according to FIG. 9, in a radialopening 37' which penetrates the wall of the cylinder guide 20. Theradial recess 27', on the other hand, is located in a core pin 11 whichalso forms an axial continuation of the cylinder core 10 in the presentcase. However, the inner radial end of the roller 61' now engages inthis radial recess 27'. The stop cams 28' on both sides can beconstructed so as to be relatively flat in this case since the fixing ofthe cylinder guide 20 with respect to rotation which is critical for thekey actuation according to FIGS. 11 to 13 is brought about via a lockingcatch 70 which is combined with the overload catch 60' and which will bedescribed more fully in the following. The slide 40' also has a stopface 42' for the roller 61' which is pressed by a similar pressurespring 54' likewise in the direction of the cylinder axis 17 accordingto FIG. 8, but the spring loading 53' brought about thereby acts on theradial slide 40' in the opposite direction compared with the firstembodiment example. The spring loading 53' according to FIG. 8 normallytends to hold the radial slide 40 in an uncoupled position according toFIG. 9.

According to FIG. 9, the critical coupling faces 46' are located at aradial projection 43 which is located at a web 47 on the side of theradial slide 40' opposite the cylinder axis 17 with reference to theeffective stop face 42' for the roller 61'. However, the correspondingcounter-coupling faces 16' are also located in this case at the core pin11, namely in a radial depression 48 which is widened angularly relativeto the projection 43. The coupling faces 46' are produced by the flanksof the projection 43. In the neutral position, the projection 43 is heldso as to be pressed out of the radial depression 48 in the core pin 11owing to the spring loading 53' acting on the radial slide 40' accordingto FIG. 9.

This uncoupled position of 46', 16' is also maintained during a forciblerotation 62 of a burglary tool, e.g., a screwdriver, which is indicatedin FIG. 8 but is not yet shown in the inserted position. As is shown inFIG. 10 and also in FIG. 9 by the corresponding rotation arrow 62, theentire locking cylinder 10, 20 can be rotated in the housing 38,wherein, in contrast to the preceding embodiment example, the roller 61'participates in the rotation. This is a result of the radial opening 37'which is now provided in the cylinder guide 20 and which carries theroller 61' along with it. The cylinder core 10 and the cylinder guide20, that is, the entire locking cylinder, are rotated in the directionindicated by the arrow 62 via the locked tumblers 15. In spite of thisfunction of the radial slide 40' with respect to the coupling 16', 46',which is the opposite of that in the first embodiment example, ananalogous locking position of the driver 50 results.

Also, in the second embodiment example the housing 30 is divided into aninner sleeve 38 and an outer sleeve 39 in the region of the driver 50.The stopping surfaces 45' which are of decisive importance for lockingare located at the lateral boundary of the aforementioned web 47 of theslide 40'. Although the associated counter-stopping surfaces 35' arealso arranged in a housing recess 67' as will be seen from FIG. 9, thishousing recess 67' is located in the region of the inner sleeve 38 incontrast to the preceding embodiment example. This locking positionbetween the stopping surfaces 35', 45' at either side is also in effectduring the forcible rotation 62 of the locking cylinder 10, 20 describedabove. The radial slide 40' is held stationary with respect to thehousing 30 and prevents a rotation of the driver 50 and accordingly amovement of its arm 51. This situation remains in effect at first whenthe proper key is inserted into the key groove 13 shown in FIG. 10 inthe neutral position N shown in FIGS. 8 to 10.

The situation changes, however, according to FIGS. 11 to 13, when theinserted key 14 finally reaches the rotation region 69 or 69' of FIGS.12 and 13. As was already described, the tumblers, as will be seen fromFIG. 11, are first aligned on the diameter of the cylinder core 10 whenthe key 14 is inserted so that the cylinder core 10 can be rotated withrespect to the cylinder guide 20 proceeding from the neutral positionshown in FIG. 9. The cylinder guide 20 is first locked by means of theaforementioned catch holder 22, 23. During the first movement phase,namely during the initial rotation 73 and 73' shown in FIGS. 12 and 13,the roller 61' which rests in the radial opening 37' of the cylinderguide 20 moves out of the radial recess 27' via its stop cam 28' andcomes to rest at the circumferential surface 18 of the cylinder core 10.The cylinder core 10 is then in an intermediate position, designated inFIG. 13 by Z, a displacement 41' of the radial side 40' opposite theradial spring loading 53' taking place up to this intermediate positionZ. This has a fourfold result.

Since the roller 61' has moved out of the radial recess 27', theoverload catch 60' mentioned in FIG. 9 is released. However, the lockingcatch 70 mentioned with reference to FIG. 9 is then activated. Thislocking catch 70 comprises the roller 61' in the radial opening 37' ofthe cylinder guide 20. However, an additional catch recess 71 is locatedat the inner cylinder surface 58 of the inner sleeve 38. The outerradial end of the roller 61' now moves into this additional catch recess71 according to FIG. 12 and accordingly fixes the cylinder guide 20 inthe inner sleeve 38 of the housing. The roller 61' is now held immovablybetween the cylinder core circumferential surface 18 on the one side andthe catch recess 71 on the other side. In this second embodimentexample, the spring loading 53' plays no part in fixing the cylinderguide 20. The other decisive key rotation 69 or 69' according to FIG.13, in which the cylinder core 10 is moved out of an intermediateposition Z determining the reversing movement into its working positionA, can now be carried out.

Another result of the displacement 41' effected in FIG. 12 consists inthat the stopping of the radial slide 40' in the inner bush 38 of thehousing is now effected in its release position. The radial slide 40'moves entirely out of the housing recess 67' so that the cooperatingstopping surfaces 35', 45' are disengaged. Finally, the displacement 41'brings about the engagement of the coupling 16', 46' described abovewith reference to FIG. 9. According to FIG. 12, this takes place becausethe coupling projection 43 of the slide 40' moves into the radialdepression 48 of the cylinder core 10. After the initial rotation 73 or73', one coupling surface 16' provided at the core pin 11 comes intocontact with one flank 46' of the projection 43, while a free gap 72remains between the two other stopping surfaces 16', 46' according toFIG. 12. Since in the present instance the key rotations can be carriedout in a mirror-inverted manner relative to one another as isillustrated in FIG. 13, the free gap 72 is constructed according to FIG.12 so as to be greater than or equal to twice the angular region of 73,73' given in both directions for the initial rotation which determinesthe lifting out of the roller 61'.

Since the coupling faces 16', 46' are effective only after the initialrotation 73 or 73', the subsequent further key rotation 69 or 69' can betransmitted to the driver 50. Consequently, during the lifting out ofthe roller 61', that is, during the initial rotation 73 and 73', thedriver arm 51 at first remains stationary in its normal position N whichis shown in solid lines in FIG. 13. Only then, during the furtherrotation 69 and 69' of the key, is the driver arm 51 moved into itsworking position, shown in dash-dot lines or dashed lines, as shown bythe swivel arrows 74, 74', characterizing its working position A.

While the foregoing description and drawings represent the preferredembodiments of the present invention, it will be obvious to thoseskilled in the art that various changes and modifications may be madetherein without departing from the true spirit and scope of the presentinvention.

What is claimed is:
 1. The locking device with a locking cylinder,especially for motor vehicle locking, wherein the locking cylinder has acylinder guide and a cylinder core which is rotatably supported thereinalong a longitudinal axis so as to be fixed axially and serves toreceive a key and can be locked with the cylinder guide viaspring-loaded tumblers when the key is withdrawn, the cylinder guidebeing rotatably supported in a stationary housing, but fixed withrespect to rotation therein via an overload catch which is brought intoan effective position, wherein the overload catch has a floatingpush-rod, a radial opening enclosing said push-rod, and a radial recesswhich receives only an inner radial end of the push-rod the radialrecess being defined by stop cams which lift the end of the push-rod outof the radial recess when a determined torque is exerted on the cylindercore or by the cylinder core on the cylinder guide and accordingly setthe overload catch in a free-running position, and when the inserted keyis rotated, the cylinder core transmits the torque, via a radiallydisplaceable and radially spring-loaded radial slide, to a driver whichperforms the locking functions in a motor vehicle wherein the radialslide has a stop face for the push-rod and presses the push-rod into theradial recess of the overload catch due to the spring-loaded radialslide, and the push-rod, which is lifted out of the radial recess at adetermined torque, displaces the radial slide, an improvement comprisingthatsaid radial slide is guided radially in the driver and is alwaysconnected with the driver so as to be fixed with respect to rotationrelative thereto; coupling faces are provided between the radial slideand one of a cylinder core and a core pin forming an extension of saidcore, stopping surfaces are provided between the radial slide and thehousing, said radial slide engages with either said coupling faces ofthe cylinder core or with the stopping surfaces of the housing; and saidradial spring loading between the driver and the radial slide pressesthe push-rod in the direction of the rotational axis of the cylindercore and holds the overload catch in the effective position.
 2. Thedevice according to claim 1, wherein, in the overload catch which fixesthe cylinder in the housing when the cylinder core is in neutralposition or is rotated via the key, but sets the cylinder guide in afree-running state in the event of forcible rotation, the radial openingpenetrates a wall of the housing and the radial recess for the innerradial end of the push-rod is incorporated in one of an outer surface ofthe cylinder guide and a guide bush forming an axial continuationthereof and faces toward an inner surface of the housing, while thespring-loaded stop face of the radial slide is located at a cylindricalouter surface of the housing.
 3. The device according to claim 2,wherein, in the overload catch, the spring loaded radial slide tends tomove the coupling faces into their coupling position and the stoppingsurfaces into their release position.
 4. The device according to claim1, wherein, in the overload catch which locks the cylinder core in aneutral position and is locked with the cylinder guide in the event of aforcible rotation but releases the cylinder guide during key rotation,the radial opening penetrates the wall of the cylinder guide and theradial recess for the inner radial end of the push-rod is incorporatedin the circumferential surface of the cylinder core or in a core pinforming an axial continuation thereof and faces toward the inner surfaceof the cylinder guide, while the spring-loaded stop face of the radialslide is located at the outer surface of the cylinder guide, and whereina catch recess which lies opposite the radial recess in the neutralposition of the cylinder core is incorporated in the inner surface ofthe housing, the outer radial end of the push-rod moves into the catchrecess in a free-running position of the overload catch generated by keyrotation and accordingly fixes the cylinder guide in the housing.
 5. Thedevice according to claim 4, wherein, in the overload catch, the springloaded radial slide tends to move the coupling faces into theiruncoupled position and the stopping surfaces into their lockingposition.
 6. The device according to claim 1, wherein the coupling facesare formed by a radial projection which is located at the radial slideand by a radial depression which is incorporated in one of the cylindercore and the core pin forming the extension thereof.
 7. The deviceaccording to claim 6, wherein the two cooperating coupling faces areproduced by two lateral flanks at a projection and by a two stop ends ofa depression.
 8. The device according to claim 7, wherein, in a couplingposition of the overload catch, a free gap is located between one flankof one projection and the stop end of the depression associatedtherewith, said free gap being at least equal to the rotational path ofthe cylinder core when the inner radial end of the push-rod is liftedout of the radial recess.
 9. The device according to claim 1, whereinthe push-rod is a roller.
 10. The device according to claim 1, wherein aradially springing catch projection projects through a wall bore hole ofthe housing at an inner surface of the housing and a neutral position ofthe cylinder guide in the housing is determined by engagement of thecatch projection and a catch depression which is incorporated in anouter surface of the cylinder guide.